[PATCH v1.1 00/14] btrfs-progs: check: Use fs/subvol trees to fix extent tree, not vice versa

[Qu Wenruo <wqu@suse.com>]

This patchset can be fetched from github:
https://github.com/adam900710/btrfs-progs/tree/file_extents_fixes

This is based on v4.20.2 tag.

Originally for fsck-tests/001-bad-file-extent-bytenr we're going to fix
it by resetting the corrupted file extent, using the disk bytenr from
data backref.

However in real world, extent tree is the most fragile one while fs tree
is more reliable.
This means fixing using extent tree can sometimes be more dangerous, and
causing extra corruption from repair.

Further more, that test case is a big blockage for any later
modification on file extent repair code.

So the goal of this patchset is to change the repair behavior from
rebuilding file extents using data backref, to dropping invalid file
extents and modify extent tree.

Despite above change, we have some small bug fixes for:
- False alert for file extents gap
- Bad data backref -> file extent search in repair mode

The patchset is mostly from Fujitsu guys (Lu, Su Yue, Su Yanjun).
My work here is:
- Solve rebase conflicts
  Mostly with DIR_ITEM hash mismatch patchset

- Commit message/comment update
  Make them a little more reader friendly

- Reorder the patchset
  Make small fixes first.

Changelog:
v1.1:
- Rebase to v4.20.2
- Run self tests for misc/mkfs/fsck group.
  The only problem is from misc/035, due to we have reverted the fix.
  It's not a regression so the patchset should still be good.

Lu Fengqi (2):
  btrfs-progs: lowmem: fix false alert about the existence of gaps in
    the check_file_extent
  btrfs-progs: tests: add case for inode lose one file extent

Qu Wenruo (1):
  btrfs-progs: Update backup roots when writing super blocks

Su Yanjun (4):
  btrfs-progs: Revert "btrfs-progs: Add repair and report function for
    orphan file extent."
  btrfs-progs: Revert "btrfs-progs: Record orphan data extent ref to
    corresponding root."
  btrfs-progs: check: fix wrong @offset used in find_possible_backrefs()
  btrfs-progs: check: Delete file extent item with unaligned disk bytenr

Su Yue (7):
  btrfs-progs: lowmem: add argument path to punch_extent_hole()
  btrfs-progs: lowmem: move nbytes check before isize check
  btrfs-progs: lowmem: fix false alert if extent item has been repaired
  btrfs-progs: lowmem: check unaligned disk_bytenr for extent_data
  btrfs-progs: lowmem: rename delete_extent_tree_item() to delete_item()
  btrfs-progs: lowmem: delete unaligned bytes extent data under repair
  btrfs-progs: fsck-test: enable lowmem repair for case 001

 check/main.c                                  | 584 +++++++++++-------
 check/mode-lowmem.c                           | 293 +++++----
 check/mode-original.h                         |  30 +-
 ctree.h                                       |  10 +-
 disk-io.c                                     |  80 ++-
 .../.lowmem_repairable                        |   0
 .../.lowmem_repairable                        |   0
 .../default_case.img                          | Bin 0 -> 3072 bytes
 8 files changed, 621 insertions(+), 376 deletions(-)
 create mode 100644 tests/fsck-tests/001-bad-file-extent-bytenr/.lowmem_repairable
 create mode 100644 tests/fsck-tests/038-missing-one-file-extent/.lowmem_repairable
 create mode 100644 tests/fsck-tests/038-missing-one-file-extent/default_case.img

-- 
2.21.0